Does anyone make a good Decora-style dimmer that doesn't require it's own
trim plate? e.g. I was looking at the display at the Home Despot and I
think it was Lutron dimmers that they carried..

They carry at least two other brands and several different models at HD:

I ve looked at several ( and bought two different types..they have: slide,
slide w/ switch/ 3 position & 4 position button and finally the one that
you just "hold down" til the light level gets to what you re looking for.
All are Decora type and all will fit in a normal Decora faceplate.
They re not in the Lutron/Gucci display but down the aisle a ways.